WO2019227537A1 - Eu3+ ion-activated bismuth fluorochloroantimonate and preparation method therefor and application thereof - Google Patents

Abstract

An Eu³⁺ ion-activated bismuth fluorochloroantimonate, a preparation method therefor and an application as a luminescent material. The chemical formula thereof is Bi_1-xEu_xTeO₃(F,Cl), wherein 0.01≤x≤0.1, and the Eu³⁺ ion-activated bismuth chlorofluoroantimonate emits red fluorescence under the excitation of near ultraviolet light. The preparation method therefor comprises: dissolving bismuth oxide in an acid, then adding ammonia water to adjust the pH to 2-3, obtaining a white colloid, filtering, then extracting a solid for washing, and drying to obtain a precursor; evenly mixing the precursor, antimony oxide and europium fluoride and calcining at 500-600°C, and then cooling to obtain the EU³⁺ ion-activated bismuth chlorofluoroantimonate.

Description

Eu       3+ ion-activated bismuth chlorochlorotellurate and preparation method and application thereof      Technical field

The invention relates to the field of inorganic light-emitting materials, in particular to a Eu ³⁺ ion-activated bismuth chlorochlorotellurate and a preparation method and application thereof.

Background technique

Luminescent materials are gaining more and more important applications in many technical fields, such as lighting, display, imaging, medical radiological images, radiation detection, and the like. Among the activating ions of the luminescent material, rare earth europium ions (Eu ³⁺ ) is one of the most important red luminescent activating ions. Eu ³⁺ ions have their unique characteristics, such as very narrow emission spectrum lines, high color purity, bright colors, strong light absorption, and high conversion efficiency. Eu ³⁺ is an indispensable red coloring ion. In addition, the fluorescence spectrum structure of Eu ³⁺ makes it a structural probe ion, which can detect the crystallographic environment of the substituted cation in the matrix lattice.

In recent years, with the development of lighting display materials, Eu ³⁺ ion-activated various fluorescent materials have received great attention. In the development of these materials, the choice of matrix materials plays an important role. Halides, or Because of its rigid lattice, oxyhalides show many unique characteristics in rare-earth-activated phosphors, such as significant physical and chemical stability, thermal stability of light emission, etc., making them an excellent material for various technical materials. The main research object. At present, the types of Eu ³⁺ ion-activated materials that can emit red fluorescence need to be expanded, and their luminous efficiency and color purity need to be improved.

Summary of the Invention

In order to solve the above technical problems, an object of the present invention is to provide a Eu ³⁺ ion-activated bismuth chlorochlorotellurate and a preparation method and application thereof. The material has high crystallinity, can emit red fluorescence, has significant luminous efficiency, and has excellent color purity High and simple preparation method.

In order to achieve the above objective, the present invention adopts the following technical solutions:

In one aspect, the present invention provides a Eu ³⁺ ion-activated bismuth chlorochlorotellurate having a chemical formula of Bi _1-x Eu _x TeO ₃ (F, Cl), where 0.01≤x≤0.1, and Eu ³⁺ ion. The activated bismuth chlorochlorotellurate emits red fluorescence when excited by near-ultraviolet light.

Further, the wavelength of near-ultraviolet light is 360-420 nm.

Further, the wavelength of the red fluorescence is 580-620 nm.

The Eu ³⁺ ion-activated bismuth chlorochlorotellurate of the present invention is a crystal, Eu ³⁺ is an activated ion, Eu ³⁺ replaces Bi ³⁺ in the crystal lattice, and x represents the number of moles of Eu ³⁺ replacing Bi ³⁺ ions. Te is positive tetravalent, and F ^- and Cl ^- ions share a crystallographic position in the crystal lattice.

In another aspect, the present invention also provides the application of the Eu ³⁺ ion-activated bismuth chlorochlorotellurate in a light-emitting material, and the excitation source of the light-emitting material is near-ultraviolet light.

Further, the wavelength of near-ultraviolet light is 360-420 nm.

Further, the luminescent material emits red fluorescence under the excitation of near-ultraviolet light.

Further, the light emitting material is a lighting display device or a photoluminescence chromaticity adjusting device.

In another aspect, the present invention also provides a method for preparing the Eu ³⁺ ion-activated bismuth chlorochlorotellurate, which is prepared by a high-temperature solid-phase method, including the following steps:

(1) dissolving bismuth oxide (Bi ₂ O ₃ ) in hydrochloric acid to form a transparent solution, and then adjusting the pH to 2-3 to obtain a white colloid, filtering and washing the solid to obtain a precursor containing bismuth ions;

(2) mixing the precursor, antimony oxide (TeO ₂ ) and europium fluoride (EuF ₃ ), calcining at 500-600 ° C., and cooling to obtain Eu ³⁺ ion-activated bismuth fluorochlorotellurate;

The molar ratio of the bismuth element, thorium fluoride and antimony oxide in the precursor is 0.9-0.99: 0.01-0.1: 1.

Further, in step (1), ammonia is added to adjust the pH.

Further, in step (2), calcination is performed in an air atmosphere.

Further, in step (2), the calcination time is 2-8 h.

The method of the present invention firstly dissolves Bi ₂ O ₃ with an acid, so that a large amount of Bi ³⁺ is formed in the solution, and then adjusts the pH to 2-3 by adding ammonia water, so as to generate a precursor containing Bi ions. The precursors TeO ₂ and EuF ₃ are calcined, so that each substance generates a crystalline product under heating conditions, that is, Eu ³⁺ ion-activated bismuth fluorochlorotellurate.

With the above solution, the present invention has at least the following advantages:

1. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate of the present invention has strong light absorption for near-ultraviolet light of 360-420nm, and can emit red fluorescence under the excitation of near-ultraviolet light, the strongest light emission. The wavelength is 613 nanometers, and its chromaticity is pure, and the luminous efficiency is remarkable.

2. The Eu ³⁺ ion-activated bismuth fluorotellurate prepared by the present invention has a lower sintering temperature (500-600 ° C), uniform particle size, and good cleanliness.

3. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate of the present invention is prepared by conventional solid-phase reaction. The equipment and process are simple, the preparation method is simple, and the operation is easy. The requirements for the equipment are low, no waste gas and waste gas are discharged, and the environment is friendly .

4. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate of the present invention can be used as a light-emitting material, and is suitable for various light-emitting devices using near-ultraviolet light as an excitation source.

The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly and can be implemented in accordance with the contents of the description, the following describes in detail the preferred embodiments of the present invention in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is an X-ray powder diffraction pattern of Eu ³⁺ ion-activated bismuth fluorotellurate prepared in Example 1 of the present invention;

2 is an electron scanning electron microscope image of Eu ³⁺ ion-activated bismuth fluorotellurate prepared in Example 1 of the present invention;

3 is an EDS electron spectrum surface scanning analysis result of Eu ³⁺ ion-activated bismuth fluorotellurate prepared in Example 1 of the present invention;

4 is an excitation spectrum diagram of Eu ³⁺ ion-activated bismuth fluorotellurate prepared in Example 1 of the present invention under monitoring at 615 nm;

FIG. 5 is a luminescence spectrum diagram of Eu ³⁺ ion-activated bismuth fluorotellurate prepared under the excitation at a wavelength of 395 nm prepared in Example 1 of the present invention.

Detailed ways

The specific embodiments of the present invention are described in further detail below with reference to the drawings and embodiments. The following examples are used to illustrate the present invention, but not to limit the scope of the present invention.

Example 1:

This embodiment provides a Eu ³⁺ ion-activated bismuth chlorochlorotellurate, whose chemical formula is Bi ₉₅ Eu _0.05 TeO ₃ (F, Cl). According to the molar ratios of Bi ³⁺ , Eu ³⁺ and Te ⁴⁺ in the chemical formula, bismuth oxide Bi ₂ O ₃ : 4.427 g, europium fluoride EuF ₃ : 0.21 g, and tellurium oxide TeO ₂ : 3.192 g, respectively. The above Eu ³⁺ ion-activated bismuth chlorochlorotellurate was prepared as follows:

First, dissolve Bi ₂ O ₃ in HCl solution and keep stirring until it is completely dissolved to form a transparent solution. Add an appropriate amount of ammonia solution to the above solution and adjust the pH of the solution to 2 to obtain a white colloidal mixed solution. The precipitate was obtained, washed several times with deionized water and absolute ethanol to obtain a white precipitate, and dried to obtain a precursor powder.

The precursor powder prepared by the above method, TeO ₂ tellurium oxide and EuF ₃ fluoride are mixed together, uniformly ground, and then the obtained mixture is pressed into a ceramic block, which is calcined in an air atmosphere. The calcination temperature is 500 ° C. and the calcination time. It was 8 hours, naturally cooled, and uniformly ground to obtain Eu ³⁺ ion-activated bismuth chlorochlorotellurate red phosphor.

FIG. 1 is an X-ray powder diffraction pattern of the above product. The test results show that the prepared sample is a single phase and has a good crystallinity.

FIG. 2 is an electron scanning electron microscope image of the above product. It can be seen from the figure that the sample is uniformly crystallized without agglomeration.

FIG. 3 is an EDS electron spectrum surface scanning analysis result of the above product, which can analyze the types of components and elements in the micro region of the material. The results show that the main constituent elements of the product of this embodiment include Bi, Eu, Te, O, F, and Cl.

FIG. 4 is an excitation spectrum obtained by monitoring the above product at 615 nm. It can be seen from the figure that the excitation source of red light emission of the material is mainly 395 nm, which indicates that the product can be used to prepare near-ultraviolet excited fluorescent lamps.

Fig. 5 shows the emission spectrum of the above product under the excitation of 395 nm. Fig. 5 shows that the main emission center of the material is in the red emission band of 615 nm.

Example 2:

This embodiment provides an Eu ³⁺ ion-activated bismuth chlorochlorotellurate, whose chemical formula is Bi _0.93 Eu _0.07 TeO ₃ (F, Cl). According to the molar ratio of Bi ³⁺ , Eu ³⁺ and Te ⁴⁺ in the chemical formula, bismuth oxide Bi ₂ O ₃ : 4.333 g, europium fluoride EuF ₃ : 0.293 g, and tellurium oxide TeO ₂ : 3.192 g, respectively. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate was prepared as follows:

First, dissolve Bi ₂ O ₃ in HCl solution and keep stirring until it is completely dissolved to form a transparent solution; add an appropriate amount of ammonia solution to the above solution, adjust the pH of the solution to 3 to obtain a white colloidal mixed solution, and let it stand for filtration. The precipitate was obtained, washed with deionized water and absolute ethanol several times to obtain a white precipitate, and dried to obtain a precursor powder.

The precursor powder prepared by the above method, TeO ₂ tellurium oxide and EuF ₃ fluoride are mixed together, uniformly ground, and then the obtained mixture is pressed into a ceramic block, which is calcined in an air atmosphere at a calcination temperature of 600 ° C. and calcined. The time is 2 hours, natural cooling, and uniform grinding to obtain Eu ³⁺ ion-activated bismuth fluorochlorotellurate red phosphor. Its phase composition, excitation spectrum, and emission spectrum are similar to those obtained in Example 1.

Example 3:

This embodiment provides an Eu ³⁺ ion-activated bismuth chlorochlorotellurate, whose chemical formula is Bi _0.9 Eu _0.1 TeO ₃ (F, Cl). According to the molar ratio of Bi ³⁺ , Eu ³⁺ and Te ⁴⁺ in the chemical formula, bismuth oxide Bi ₂ O ₃ : 4.19 g, europium fluoride EuF ₃ : 0.418 g, and tellurium oxide TeO ₂ : 3.192 g, respectively. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate was prepared as follows:

First, dissolve Bi ₂ O ₃ in HCl solution and keep stirring until it is completely dissolved to form a transparent solution. Add an appropriate amount of ammonia solution to the above solution and adjust the pH of the solution to 2.5 to obtain a white colloidal mixed solution. The precipitate was obtained, washed with deionized water and absolute ethanol several times to obtain a white precipitate, and dried to obtain a precursor powder.

The precursor powder prepared by the above method, TeO ₂ tellurium oxide, and EuF ₃ fluorene are mixed together, uniformly ground, and then the obtained mixture is pressed into a ceramic block, which is calcined in an air atmosphere at a calcination temperature of 550 ° C. and calcined. The time is 5 hours, natural cooling, and uniform grinding to obtain Eu ³⁺ ion-activated bismuth chlorochlorotellurate red phosphor. Its phase composition, excitation spectrum, and emission spectrum are similar to those of the product in Example 1.

Example 4:

This embodiment provides an Eu ³⁺ ion-activated bismuth chlorochlorotellurate, whose chemical formula is Bi _0.99 Eu _0.01 TeO ₃ (F, Cl). According to the molar ratio of Bi ³⁺ , Eu ³⁺ and Te ⁴⁺ in the chemical formula, bismuth oxide Bi ₂ O ₃ : 4.613 g, europium fluoride EuF ₃ : 0.05 g, and tellurium oxide TeO ₂ : 3.192 g were weighed respectively. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate was prepared as follows:

First, dissolve Bi ₂ O ₃ in HCl solution and keep stirring until it is completely dissolved to form a transparent solution; add an appropriate amount of ammonia solution to the above solution, adjust the pH of the solution to 3 to obtain a white colloidal mixed solution, and let it stand for filtration. The precipitate was obtained, washed with deionized water and absolute ethanol several times to obtain a white precipitate, and dried to obtain a precursor powder.

The precursor powder prepared by the above method, TeO ₂ tellurium oxide and EuF ₃ fluoride are mixed together, uniformly ground, and then the obtained mixture is pressed into a ceramic block, which is calcined in an air atmosphere. The calcination temperature is 530 ° C. and the calcination time. It was naturally cooled for 6 hours and uniformly ground to obtain Eu ³⁺ ion-activated bismuth chlorochlorotellurate red phosphor. Its phase composition, excitation spectrum, and emission spectrum are similar to those of the product in Example 1.

Example 5:

This embodiment provides a Eu ³⁺ ion-activated bismuth chlorochlorotellurate, whose chemical formula is Bi _0.97 Eu _0.03 TeO ₃ (F, Cl). According to the molar ratio of Bi ³⁺ , Eu ³⁺ and Te ⁴⁺ in the chemical formula, bismuth oxide Bi ₂ O ₃ : 4.52 g, europium fluoride EuF ₃ : 0.125 g, and tellurium oxide TeO ₂ : 3.192 g, respectively. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate was prepared as follows:

First, dissolve Bi ₂ O ₃ in HCl solution and keep stirring until it is completely dissolved to form a transparent solution. Add an appropriate amount of ammonia solution to the above solution and adjust the pH of the solution to 2.5 to obtain a white colloidal mixed solution. The precipitate was obtained, washed with deionized water and absolute ethanol several times to obtain a white precipitate, and dried to obtain a precursor powder.

The precursor powder prepared by the above method, TeO ₂ tellurium oxide and EuF ₃ fluoride are mixed together, uniformly ground, and then the obtained mixture is pressed into a ceramic block, which is calcined in an air atmosphere. The calcination temperature is 530 ° C., and the calcination is performed. The time is 7 hours, and the mixture is naturally cooled and uniformly ground to obtain Eu ³⁺ ion-activated bismuth chlorochlorotellurate red phosphor. Its phase composition, excitation spectrum, and emission spectrum are similar to those of the product in Example 1.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the technical principles of the present invention. And modifications, these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (8)

1. An Eu ³⁺ ion-activated bismuth chlorochlorotellurate, characterized in that its chemical formula is Bi _1-x Eu _x TeO ₃ (F, Cl), where 0.01≤x≤0.1, and the Eu ³⁺ ion-activated Bismuth fluochlorotellurate emits red fluorescence under the excitation of near-ultraviolet light.
2. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate according to claim 1, wherein the wavelength of the near-ultraviolet light is 360-420 nm.
3. The Eu ³⁺ ion-activated bismuth chlorochlorotellurate according to claim 1, wherein the wavelength of the red fluorescence is 580-620 nm.
4. The use of the Eu ³⁺ ion-activated bismuth chlorotellurate according to any one of claims 1 to 3 as a light-emitting material, wherein the excitation source of the light-emitting material is near-ultraviolet light.
5. A method for preparing Eu ³⁺ ion-activated bismuth chlorochlorotellurate according to any one of claims 1-3, comprising the following steps:

   (1) dissolving bismuth oxide in hydrochloric acid, then adjusting the pH to 2-3 to obtain a white colloid, filtering and washing the solid, and drying to obtain a precursor containing bismuth ions;

   (2) mixing the precursor, antimony oxide and thorium fluoride, calcining at 500-600 ° C., and obtaining the Eu ³⁺ ion-activated bismuth chlorochlorotellurate after cooling;

   Wherein, the molar ratio of the bismuth element, thorium fluoride and antimony oxide in the precursor is 0.9-0.99: 0.01-0.1: 1.
6. The method according to claim 5, wherein in step (1), ammonia is added to adjust the pH.
7. The method according to claim 5, characterized in that, in step (2), calcination is performed in an air atmosphere.
8. The preparation method according to claim 5, characterized in that, in the step (2), the calcination time is 2-8h.

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